Taxiing
Taxiing is movement on the ground between stand and runway. Despite low speed it is a frequent cause of damage (collisions, runway incursions, wake effects from other aircraft).
Sources: ICAO Annex 14, ICAO Doc 9981 PANS-Aerodromes, FAA-H-8083-3B Chapter 2.
Before moving
- Clearance from tower/ground ("Request taxi, runway 26").
- ATIS listened (wind, runway in use, QNH, NOTAMs).
- Taxi route marked on the airfield plan (apron chart).
- Brake test immediately after moving (3–5 m): brief brake, feel response.
Carburettor heat during taxi — OFF
During taxi, carburettor heat (carb heat) and similar fresh-air bypasses must remain OFF. Reason: carb heat draws air not through the air filter but directly from the engine compartment — allowing sand, dust and small particles from the ground to enter the engine unfiltered and damage cylinders, valves and plugs.
→ Carb heat OFF during taxi. It is briefly tested at run-up (see next lesson) — then OFF again until the approach (where carb-icing protection is needed).
Speed
- Apron: walking pace (max 5 kt).
- Taxiway: max 20 kt (rule of thumb; consult POH).
- Tight spots (intersections, turns): slow further.
- Stand-off: keep minimum distance behind waiting aircraft → avoid wake zones.
- Behind larger aircraft (higher wake-turbulence class): keep at least 200 m distance (see lesson "Wake Turbulence").
Control
- Nose-wheel steering via pedals (single-engine).
- Differential brakes for tight turns (sparingly).
- Elevator (yoke) per wind:
Wind control during taxi (rule "Quartering Wind Corrections")
| Wind direction relative to aircraft | Ailerons | Elevator |
|---|---|---|
| Front-right quarter (headwind from right) | Ailerons right (into wind) | neutral / slightly up |
| Front-left quarter (headwind from left) | Ailerons left (into wind) | neutral / slightly up |
| Rear-right quarter (tailwind from right) | Ailerons left (away from wind) | forward / down |
| Rear-left quarter (tailwind from left) | Ailerons right (away from wind) | forward / down |
Mnemonic: "Climb into the wind, dive away from it." — ailerons into wind quarter with headwind, away with tailwind.
Source: FAA-H-8083-3B Ch. 2.
Taxiing on uneven ground
On uneven ground (grass, gravel, ruts, mole hills) the pilot must take special care to avoid propeller damage, nose-gear sinking, or tipping over:
- Pull elevator fully back ("yoke fully back") — nose stays up, less load on nose gear and propeller.
- Taxi slowly — low speed, every bump is better absorbed.
- Set power cautiously — no abrupt acceleration, otherwise nose dig or jam.
- Watch tailwind component — tailwind can press the nose down further; hold yoke back accordingly.
Run-up position
- Designated run-up bay before the runway (off the active runway).
- Nose into wind so the engine cools and propeller wash doesn't endanger other aircraft.
- Brakes set and aligned on a horizontal line.
- Run-up checks performed (next lesson).
Special cases
- Bad weather: visibility reduced → caution speed; on icy runway brakes carefully; wind correction intensified in storms.
- Night taxi: all taxi and position lights on; anti-collision light on; landing light on at runway crossing, otherwise off.
- Holding point: stop before the holding point and call "ready for departure".
Communication with tower
Standard phraseology (Subject 090):
- "Request taxi for VFR via Romeo Bravo runway 26."
- "Holding short runway 26."
- "Ready for departure."
Risks
- Runway incursion: biggest ground-operations risk area! ICAO/Eurocontrol Runway Safety Programme.
- Propeller damage: from upstanding stones, screws on the ground — especially on uneven surface.
- Wake turbulence of a heavier aircraft ahead — see lesson "Wake Turbulence".